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Comment by eunoia | Hacker News Reader

> go again the same day.

That seems like a stretch. What is the actual turnaround time for Starship? fwiw the Shuttle had a lot of lofty promises of reusability that were technically true as long as you didn't consider how long the turnaround time was.

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The shuttle boosters required rebuilding / refueling (which is solid rocket goop) and the fuel tank was completely lost and required rebuilding. The head shield tiles were extremely fragile on the shuttle.

It was never a fully reusable design, just more reusable than before.

SpaceX plans to have no parts that are lost each flight and is working to make the tiles mostly standardized and less sensitive to faults.

Are they going to replace all the tiles before it can relaunch? And what about the engine nozzles? They must be taking quite the beating.

No doubt SpaceX has very smart people working on this and I'm not an expert in material science, but I just find it hard to believe that same day turnaround could be possible. If true, that would really make us a confirmed space faring civilization. We could actually start colonizing Mars.

> what about the engine nozzles?

Falcon 9 has reflown in just over 4 hours [1]. (EDIT: Operational turnaround. Nozzles have been turned around allegedly without refurb in 3 weeks.)

[1] https://en.m.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_...

No, those were separate craft, on opposite sides of the country. It demonstrates an ability to manage multiple missions at once, but not rapid booster turnaround.

https://www.space.com/spacex-starlink-launch-doubleheader-ju...

They've since done two flights in about an hour with https://spaceflightnow.com/tag/starlink-9-5/ and https://spaceflightnow.com/tag/starlink-8-10/

I think the first-stage turnaround record is something like two weeks.

https://en.wikipedia.org/wiki/List_of_Falcon_9_first-stage_b...

> B1062 booster holds the record for fastest turnaround at 21 days. It launched on 8 April and again on 29 April 2022.

For context on JumpCrisscross's comment in this thread: the 4 hours is between two separate launches on two separate rockets. This is absolutely not refurbishing and launching the same rocket 4 hours apart.

Seems like the actual record for turning around the same booster is 21 days, which is still quite impressive.

https://www.teslarati.com/spacex-falcon-9-new-booster-turnar...

The heat tiles are reusable, just like the Shuttle's. They are basically just a material that insulates very well, instead of a traditional ablative heat shield that burns away. With the space shuttle they ended up spending a lot of time inspecting each tile for damage and replacing cracked tiles. SpaceX has a modern iteration of the same material, hopefully with fewer cracks.

Other factors that work in SpaceX's favor are 1) that most launches will be unmanned, meaning they can take bigger risks than the Space Shuttle program; 2) that the steel body of Starship can handle higher temperatures than the Space Shuttle's aluminum, so a compromised heat shield is more tolerable; 3) for now they have a secondary ablative heat shield below the tiles (that does have to be replaced when it gets used, but that should only happen when tiles fall off)

Beware the dunning-kruger effect. There is a lot more to colonizing mars than reusable rockets. Just saying..

Some of SpaceX's first stages are getting close to the individual Shuttles' launch counts, with substantially less turnaround time and cost than Shuttle ever had.

Starship has work to do, but it's hard to argue they're not at least on the right path.

Also, less cost in life.

SpaceX was able to re-fly a Falcon 9 in 3 weeks, and it was reported[0] that the refurb process only took 9 days. So they're well on their way.

It's also worth noting that Booster (the first stage), Starship (the second stage) and Raptor (the rocket engine) were all designed with the benefit of the above experience and with the goal of same-day reuse in mind. They know where all of the refurb time went and where the bottlenecks are.

I have no doubt that they can reduce the turnaround further, but the goal of same-day re-flight does seem mighty ambitious.

[0] https://www.teslarati.com/spacex-falcon-9-new-booster-turnar...

With the Falcon 9 they're already at over 100 launches this year. It's multiple rockets, but the turn around is pretty quick and getting quicker every year. They're designing starship from the start with same day turnaround in mind. I wouldn't bet against it I guess.

For the Super Heavy booster, SpaceX is targeting a <1hr turnaround time. For the ship, it gets a bit more complex. Ships have to make complete orbits before returning, and generally they have to be loaded with cargo as well. Tanker Starships for lunar/Mars missions will probably have pretty quick turnaround given that fuel can be loaded on the pad; other ships will have significantly longer turnarounds.

It's a good question. The hurdle to clear for same-day reuse will be the heat shield. SpaceX hasn't yet demonstrated that Starship can reenter the atmosphere and remain fully intact. Doing it while sustaining near zero wear on the heat shield will be even harder. But I think it is not impossible, and I don't know of any other obvious blockers for same day reuse.

Even if they can reuse the booster, it would be huge.

They'll likely reuse the booster on the same day well before the starship portion. No heat shield on the booster. Some starships will likely stay in space for a long time before returning.

Musk has said they're aiming for hundreds of reuses for the booster and dozens for the ship.

It's certainly looked fully intact when reaching ground.

When they manage to do the intended landing it should be pretty unharmed, but I'm sure it will take a while before same-day reuse is attempted.

One of the flaps burned through again. Not as bad as the first time. The hinge area seems like the hardest challenge.

Is this a bit of over engineering? How much is drag reduced during liftoff by having the flaps folded?

The reason the flaps move is to provide attitude and speed control during reentry. Like a skydiver spreading their arms and legs.

oh, you mean like actual flaps of pretty much any aircraft. doh! i was thinking it was like the folding of the wings for planes on an aircraft carrier. sometimes my brain, boy, i don't know

It was a flap hinge that burnt through, not the flap. They have a solution for block 2 which we'll likely see in test 7 -- move the flap slightly further back so that the hinge isn't in direct flow.

Zero wear is not necessary. The tiles can be thicker than the minimum, and be reusable until they wear down to the minimum. Like the brake pads on your car.

The previous flight was October 13, 2024, so while I can't speak to every day, one month turnaround is a reality.

It's a completely different booster and ship that's flying.

And both are already outdated - flight seven (Ship 33) introduces a new generation of hardware. They're moving fast with these.

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